Preserved wood and process of making same



reunite Aug. 7, i923.-

1,464,044. UNITED STATES-PATENT OFFICE.-

no nm r a. mu, m, or NORFOLK, vrnemm, assrenon or onnsnerr ro onner a.MARE, or nonronx, vrnenrm.

PRESERVED WOOD AND PROCESS or MAKING SAME.

We Drawing application filed July 11, 1918, Serial No. 244,465. RenewedDecember to, more.

To all whom it mag concern:

Be it known that ROBERT A, Mann, Jr, a citizen of the United States ofAmerica, residin at Norfolk, in the county of Norfolk 6 and tateotVirginia, has invented certain new and useful Improvements in PreservedWood and Processes of Making Same, of which the following is aspecification. I The present invention concerns a new process ofpreserving wood by impregnating the same with a particular mixture ofmaterial, whereby its cells, ducts and pores are encysted with a mixturewhich hardens upon cooling, and thereby prevents the .ingross ofwood-destroying organisms, and which mixture is impervious to moisturei,

and which also carries a material capable o welg l a Parts.

Parafin wax Fuel oil of paraflin base 12 to 15 Asphalt to Fuel oil ofasphalt base 12 to 15 Creosote, (coal tar) from which the naphthalenehas been removed 10 to 15 Rosin 10 to'12 Diatomaceous earth, (90%passing a 200 mesh screen) Of the above materials the entire list may beused, or the parafiin and paraffin-base 011 may be omitted, ortheasphalt and asphaltbase oil may be omitted. These two pairs of materialsseem to" supplement each other, and either or both airs thereof may beused in the mixture. fprefer to employ both pairs, for eneral purposes,but if color 1s objectionab e, T can omit the asphalt and asphalt-baseoil. Since parafin and parami base oil are more expensive, T may omltthese, and if either pair of materials 1s omittill ted, I prefer toemploy the other in about double the amount above stated.

- llncarrying my process into effect, ll prefer to mix the parafin andparaffin-base oil, hot, by stirring. I prefer to separately mix theasphalt and asphalt-base oil, also hot. The

diatomaceous earth is then added. I prefer to separately mix thecreosote (the naphthalene having preferably been removed therefrom) withthe rosin. The rosin-creosote mixture is then added to the mixture ofother materials.

The wood, which ma mg not being necessary; immersed in the bath of themixture while such mixture is hot, and the mixture maintained hot untilthe desired amount of impregnation is effected, the length of timedepending upon various conditions, such as size, water content, andcloseness of texture of the wood, temperature ofthe bath, and otherconditions. The impregnation may" be, and for wood to be used in seawater, is preferably complete. For posts, piles, etc., the wood may hestood on end in the hot bath,

be green (seasonof a depth sulhcient to impregnate a part onlyofthe'length of the pieces.

(VllDhOHt limiting myselt to particular temis then preferably peratures,I mention as especially suitable a temperature of 120 to 1&0 (3., forthe bath, and at this temperature the impregnation is rapid andcomplete. For a veryheavy impregnation, I may employ the temperaturesabove stated, and allow the bath to cool, nearly to the solidificationtemperature of the mixture composing the bath before removing the woodfrom the bath.

My process is applicable to all varieties of Wood, and I call attentionto the simplicity of the process llt is not necessary to employ costlypressure resisting treating receptacles, air compressors, vacuum pumps,etc., as are usually necessary, to efiect a substantially completeimpregnation with creosote. The materials used are all relatively cheapand easily obtainable in large quantities. The process is accordinglyvery economical. I

In some of the appended claims, the term solidifiable petroleum base isintended to cover both paraffin and asphalt. W here ll refer to the useof creosote from which the naphthalene has been removed, ll intend toimply that all or a considerable part of the naphthalene has beenremoved therefrom. In practice absolutely every last trace of thlsmaterial cannot be removed, and if some of the naphthalene remains, itis of no mate'- rial disadvantage. The wood-preserving 1ndustr generallywill not accept this material, ut it works very well in the presentprocess.

In addition to the materials above men tioned, other materials can beadded to produce special effects, and I intend for the claims to coverthe addition or omission of such other materials.

While the diatomaceous earth, (kieselguhr) is not soluble in themenstruum, it is such a fine powder that it is carried into the smallestcavities of the wood. The material is so fine that it will penetratewherever the liquids penetrate. Thishas been demonstrated by microscopicexamination of the cell contents of treated wood, taken near the centerof relatively large pieces.

When the wood is removed from the bath,

the absorbed material solidifies, filling the cells and cavities with animpenetrable deposit, that will effectively prevent the entrance ofWood-destroying agencies. This also adds strength and resiliency to thewood.

In the above example, I have given the proportions that I have foundmost useful,

but I do not limit myself to these proper tions.

Fuel oil, as used herein, is intended to mean petroleum oil from whichthe gasoline and kerosene (and if desired also some of the heavierfractions) have been removed.

Crude petroleum couldbe used, but the gasoline and perhaps some of theother fractions would be lost. 'The use of crude oil' would also add tothe fire risk, and would be inferior, since the lighter fractions willnot readily solidify, and would not remain permanently. Fuel oil isaccordingly to be recommended.

I claim 1. A process of preserving wood, comprising the impregnationthereof with a solidifiable material, fluid when hot, comprising asolidifiablc petroleum base and a petroleum oil of that base, creosote,rosin and diatomaceous earth.

2. lVood impregnated with a resolidified mixture comprising asolidifiable petroleum base a petroleum oil of that base, creosote,rosin and diatomaceous earth.

3. A process of preserving wood which comprises impregnating with a.material comprising asphalt, asphalt-base oil, creosote from which amaterial part of the naphthalene content has been removed, diatomaceousearth and rosin.

4. \Vood impregnated with asphalt, asphalt-base oil, denaphthalenatedcreosote, rosin and diatomaceous earth.

5. A process of preserving wood comprising the impregnation thereof witha solidifiable material, fluid when hot, comp-rising a soliditiablepetroleum base, and a petroleum oil of that base, rosin, diatomaceousearth, and creosote from which a material part at least of thenaphthalene content has been removed.

6. \Vood impregnated with a resolidified mixture comprising asolidifiable petroleum base, a petroleum oil of that base, rosin,diatomaceous earth and creosote from which a material part at least ofthe naphthalene content has been removed.

In testimony whereof I affix my signature.

ROBERT A. MARR, JR.

